I would assert taht the Grand Canyon is a problem for young earthers, actually. Trying to explain all of the features of the Grand Canyon ina young earth paradigm would be exceedingly difficult. Just the angular uncomformities all by themselves negate the possibility that most YEers assert where all of the layers were laid sown in the flood. There would be no way for the layers to have been deposited, eroded, then additional layers deposited on top, hardened and then a canyon cut through the whole stack. Even the lowest sedimentary layers below the unconformities contain fossils eliminating the possible work around of some that these layers were original.
The meanders in the canyon and the steep sides of the canyon negate the possibility that the canyon formed rapidly by runoff through soft deposits. Soft deposits would yield straighter runs rather than the meanders and would not be strong enough to result in the high, vertical faces.
Some of the layers have rock of volcanic origin scattered in there. Hard to do this while sedimentary layers are being rapidly laid down.
When solids are suspended in water (or any fluid) the largest settle out first and the smallest take the longest to settle out. If all of these layers were laid down at once, the layers should be sorted with the coarsest material at the bottom and the finest at the top. This is not so.
The layers are sorted according to their ratios of radioactive materials. Hard for water to do this.
The layers preserve many kinds of fossils including trace fossils. It is quite hard to get trace footprints and raindrops and such when under thousands of feet of raging flood.
DIfferent layers also show records of being formed under specifc types of ecology. For instance, some layers were formed while the area was in a shallow marine environment, like a coastline. Other show very different ecological niches. If all these layers were laid down in a raging flood, there would not be the ability to leave such finely tuned markers.
